package com.htu.mapreduce;
	import java.io.IOException;  
	import java.util.StringTokenizer;  
	import org.apache.hadoop.fs.Path;  
	import org.apache.hadoop.io.IntWritable;  
	import org.apache.hadoop.io.Text;  
	import org.apache.hadoop.mapreduce.Job;  
	import org.apache.hadoop.mapreduce.Mapper;  
	import org.apache.hadoop.mapreduce.Reducer;  
	import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;  
	import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;  
	
	
	public class WordCount {  
		
	    public static void main(String[] args) throws IOException, ClassNotFoundException, InterruptedException {  
	        Job job = Job.getInstance();  
	        job.setJobName("WordCount");  
	        job.setJarByClass(WordCount.class);  
	        job.setMapperClass(doMapper.class);  
	        job.setReducerClass(doReducer.class);  
	        job.setOutputKeyClass(Text.class);  
	        job.setOutputValueClass(IntWritable.class);  
	        Path in = new Path("hdfs://localhost:9000/mymapreduce1/in/buyer_favorite1");   //文件所在
	        Path out = new Path("hdfs://localhost:9000/mymapreduce1/out");  //输出
	        FileInputFormat.addInputPath(job, in);  //MapReduce读取输入文件路径
	        FileOutputFormat.setOutputPath(job, out);  //输出同上
	        System.exit(job.waitForCompletion(true) ? 0 : 1);  
	    }  
	    public static class doMapper extends Mapper<Object, Text, Text, IntWritable>{  
	        public static final IntWritable one = new IntWritable(1);  
	        public static Text word = new Text();  
	        @Override  //重写
	        protected void map(Object key, Text value, Context context)  throws IOException, InterruptedException {  
	            StringTokenizer tokenizer = new StringTokenizer(value.toString(), " ");  
	                word.set(tokenizer.nextToken());  
	                context.write(word, one);  
	        }  
	    }  
	    public static class doReducer extends Reducer<Text, IntWritable, Text, IntWritable>{  
	        private IntWritable result = new IntWritable();  
	        @Override //重写
	        protected void reduce(Text key, Iterable<IntWritable> values, Context context)  
	        throws IOException, InterruptedException {  
	        int sum = 0;  
	        for (IntWritable value : values) {  
	        sum += value.get();  
	        }  
	        result.set(sum);  
	        context.write(key, result);  
	        }  
        }
}